Persons that are traveling from location to location during a workday have difficulty in being reached. There has been widespread use of phone answering devices but the drawback of these is that some people do not want to leave messages. Attempts have been made to provide call forwarding whereby a person out in the field with access to a phone may have his calls forwarded directly to his present location, which in operation does not require a person present at the forwarding phone. It is preferred to have this call forwarding accomplished in a relatively simple manner without the caller knowing that the transfer has been made.
Prior known call forwarding technology with remote programming change capability has required the use of a switch box at the forwarding phone and two telephone lines from the phone company to the switch box.
Engel U.S. Pat. No. 2,124,913 discloses a relay at the telephone exchange and a calling relay at the forwarding station that is energized by the caller so that, when a call is made by the calling station, the device at the forwarding station instructs the exchange to dial a different number.
Ballin et al. U.S. Pat. No. 3,510,598 discloses a telephone call diverter and answering device which answers a call with a greeting prerecorded on a storage drum. The new telephone number is also stored on the storage drum, and means are provided whereby a number is automatically dialed to connect the caller to the new number and for remotely changing the transfer number.
Sousa U.S. Pat. No. 3,959,600 discloses means for reprogramming the transfer number in a two-telephone line system.
Recently available services by some telephone companies provide call forwarding on a single line, but there are no known call forwarding devices presently available, using a single line, that are reprogrammable either remotely or locally.